[rfc,v6,0/4] add frag page support in page pool

Message

Yunsheng Lin July 20, 2021, 3:35 a.m. UTC

This patchset adds frag page support in page pool and
enable skb's page frag recycling based on page pool in
hns3 drvier.

RFC v6:
1. Disable frag page support in system 32-bit arch and
   64-bit DMA.

RFC v5:
1. Rename dma_addr[0] to pp_frag_count and adjust codes
   according to the rename.

RFC v4:
1. Use the dma_addr[1] to store bias.
2. Default to a pagecnt_bias of PAGE_SIZE - 1.
3. other minor comment suggested by Alexander.

RFC v3:
1. Implement the semantic of "page recycling only wait for the
   page pool user instead of all user of a page"
2. Support the frag allocation of different sizes
3. Merge patch 4 & 5 to one patch as it does not make sense to
   use page_pool_dev_alloc_pages() API directly with elevated
   refcnt.
4. other minor comment suggested by Alexander.

RFC v2:
1. Split patch 1 to more reviewable one.
2. Repurpose the lower 12 bits of the dma address to store the
   pagecnt_bias as suggested by Alexander.
3. support recycling to pool->alloc for elevated refcnt case
   too.

Yunsheng Lin (4):
  page_pool: keep pp info as long as page pool owns the page
  page_pool: add interface to manipulate frag count in page pool
  page_pool: add frag page recycling support in page pool
  net: hns3: support skb's frag page recycling based on page pool

 drivers/net/ethernet/hisilicon/hns3/hns3_enet.c |  82 +++++++++++++++--
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.h |   3 +
 drivers/net/ethernet/marvell/mvneta.c           |   6 +-
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c |   2 +-
 drivers/net/ethernet/ti/cpsw.c                  |   2 +-
 drivers/net/ethernet/ti/cpsw_new.c              |   2 +-
 include/linux/mm_types.h                        |  18 ++--
 include/linux/skbuff.h                          |   4 +-
 include/net/page_pool.h                         |  65 +++++++++++---
 net/core/page_pool.c                            | 112 +++++++++++++++++++++++-
 10 files changed, 257 insertions(+), 39 deletions(-)